A Lightweight Design on Mobile Power Supply with Fuel Cell Energy Storage Based on Modular Multilevel Converter

In this paper, a MMC based fuel cell (FC) system (MMC-FCs) is proposed for mobile power supply. The synchronous switch modulation based on high-frequency link (HFL) can realize the voltage control of DC bus of interconnected full-bridge. It also helps to suppress the fundamental and 2ndorder-frequency ripple current of the sub-module (SM), thus greatly reducing the size of the SM capacitor, so as to realize the lightweight of the system. The fuel cell system uses partial power control to regulate the output energy, which reduces the power and power loss of fuel cell conversion. In this paper, the topology of MMC-FCs, the principle of SM ripple current cancellation, the partial power conversion (PPC) mechanism of FC, the parameters of SM capacitance and FC partial power conversion are analyzed. The lightweight effect of the system is evaluated from the perspective of system volume. Finally, simulation and experimental results verify the effectiveness of the scheme.